A first wireless communication device may transmit an aggregate data unit including a plurality of data units to a second wireless communication device. For example, the first wireless communication device may transmit an aggregate medium access control (MAC) protocol data unit (MPDU) (A-MPDU) including an aggregation of a plurality of MPDUs.
The second wireless communication unit may successfully receive one or more of the MPDUs, and may transmit back to the first wireless communication device an acknowledgment, e.g., a block acknowledgement (BA), acknowledging the successfully received MPDUs.
The first wireless communication device may retransmit one or more MPDUs, which were not acknowledged by the BA, e.g., as part of a subsequent A-MPDU.